Thermal Management of GaN-on-Si High Electron Mobility Transistor by Copper Filled Micro-Trench Structure

• Published in: Scientific reports 2019-12, Vol.9 (1), p.19691-9, Article 19691
• Main Authors: Mohanty, Srikant Kumar, Chen, Yu-Yan, Yeh, Ping-Hung, Horng, Ray-Hua
• Format: Article
• Language: English
• Subjects: 639/166; 639/301/1005; Copper; Etching; Humanities and Social Sciences; Mobility; multidisciplinary; Science; Science (multidisciplinary); Silicon; Transistors
• ISSN: 2045-2322; 2045-2322
• DOI: 10.1038/s41598-019-56292-3

Self-heating effect is a major limitation in achieving the full performance potential of high power GaN power devices. In this work, we reported a micro-trench structure fabricated on the silicon substrate of an AlGaN/GaN high electron mobility transistor (HEMT) via deep reactive ion etching, which was subsequently filled with high thermal conductive material, copper using the electroplating process. From the current-voltage characteristics, the saturation drain current was improved by approximately 17% with the copper filled micro-trench structure due to efficient heat dissipation. The I DS difference between the pulse and DC bias measurement was about 21% at high bias V DS due to the self-heating effect. In contrast, the difference was reduced to approximately 8% for the devices with the implementation of the proposed structure. Using Micro-Raman thermometry, we showed that temperature near the drain edge of the channel can be lowered by approximately ~22 °C in a HEMT operating at ~10.6 Wmm −1 after the implementation of the trench structure. An effective method for the improvement of thermal management to enhance the performance of GaN-on-Silicon HEMTs was demonstrated.